Financial Instruments and Risk Management (Schedule of Fair Value of Assets and Liabilities Measured on a Recurring Basis) (Details) - Level 2 - Recurring fair value measurement - USD ($) $ in Millions	Sep. 30, 2025	Sep. 30, 2024
Derivative [Line Items]
Deferred compensation	$ (20.7)	$ (21.1)
Net liabilities at estimated fair value	(22.1)	(23.4)
FX contract
Derivative [Line Items]
Estimated fair value of derivatives	$ (1.4)	$ (2.3)